Marine Protected Area (MPA) size optimization tool

A simple, individual-based model together with the latest field data on home ranges, densities and schooling behaviour in 66 coral reef fishes was created to specify the relationship between reserve size and conservation effectiveness. Conservation effectiveness was measured using a simple spatial model to determine numbers of individual fish a given reserve can be expected to protect. These numbers were then analysed relative to locally expected population sizes, the fishery value, and functional role of these representative species. The results gave reason for concern over the protection status of most fishery species in standard no-take MPAs around the world, allowing to specify that larger MPAs (> 2km wide) are likely to achieve much better conservation outcomes. Importantly, the study further used outcomes to derive simple regression coefficients, which can be used in combination with the mean home range and density, and even just the maximum length, of coral reef fishes to reproduce and extrapolate simulation results. These coefficients are the basis of the CCRES MPA size optimization tool for supporting locally effective decision making.